Eddy's research I（素数打表）

港控/mmm° 2022-08-05 07:28 142阅读 0赞

# Eddy's research I #

**Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)  
Total Submission(s): 7398    Accepted Submission(s): 4477**

Problem Description

Eddy's interest is very extensive, recently he is interested in prime number. Eddy discover the all number owned can be divided into the multiply of prime number, but he can't write program, so Eddy has to ask intelligent you to help him, he asks you to write a program which can do the number to divided into the multiply of prime number factor .

Input

The input will contain a number 1 < x<= 65535 per line representing the number of elements of the set.

Output

You have to print a line in the output for each entry with the answer to the previous question.

Sample Input

11
    9412

Sample Output

11
    2*2*13*181

Author

eddy

#include<cstdio>
    #include<iostream>
    #include<cstring>
    #include<string>
    #include<cmath>
    using namespace std;
    int a[65540]={1,1},prim[65540];
    int main()
    {
        int i,len=0,n,flag;
        long long j;
        memset(a,0,sizeof(a));//标记是否为素数
        memset(prim,0,sizeof(prim));//记录素数
        for(i=2;i<=sqrt(65535);i++)//由于i的范围问题，导致程序崩溃了！换成sqrt就可以了！
        {
            for(j=i*i;j<=65535;j+=i)
            {
                a[j]=1;
            }
        }
        for(i=2;i<=65535;i++)
        {
            if(!a[i])
            {
                prim[len++]=i;
            }
        }
        while(cin>>n)
        {
            flag=0;
           if(!a[n])
           {
               cout<<n<<endl;
           }
           else
           {
               for(i=0;i<len;i++)
               {
                   while(n%prim[i]==0)
                   {
                        if(flag)
                        {
                            cout<<"*"<<prim[i];
                            n/=prim[i];
                        }
                        else
                        {
                            cout<<prim[i];
                            flag++;
                            n/=prim[i];
                        }
                    }
               }
               cout<<endl;
           }
        }
    }